WORLD HISTORY

Detailed explanation-1: -During this movement, caterpillar secretes fibre made of protein which hardens on exposure to air and becomes silk fibre. The caterpillar completely covers itself by silk fibres and turn into pupa. This covering is known as cocoon. The silk yarn (thread) is obtained from the cocoon of the silk moth.

Detailed explanation-2: -Comprised of a natural protein fiber, silk mainly consists of fibroin, which is a protein that certain types of insect larvae secrete to make cocoons. While other insects also produce silk-like substances, most of the world’s silk is derived from Bombyx mori larvae, which are worms that only live on mulberry trees.

Detailed explanation-3: -Silk processing: The cocoons are held under the sun or boiled or exposed to steam. The silk fibres separate. They obtain threads from a cocoon to use them as silk through the process is known as “reeling the silk. Reeling is done in unique apparatuses, which unwind the threads or fibres of silk from the cocoon.

Detailed explanation-4: -Silk is obtained from cocoon(pupa, chrysalis) of Bombyx mori which is the mulberry silkworm. Caterpillar of these silkworms feeds on mulberry leaves, it’s salivary gland secretes liquid silk. The salivary gland (labial gland) is modified forming the silk gland of the larva. Silk is obtained from the cocoon.